The treatment, including oral chemotherapy, involved downing 25 tablets before breakfast to bring his blood count down to a low level to allow the harvest of stem cells, which were reproduced before being put back into Kevin's system.
"That bone-marrow transplant was the worst month ever," Esther said.
And while Kevin got on with his treatment, having lost 15kg along the way, Esther was determined to put her energy into fundraising for Leukaemia and Blood Cancer New Zealand (LBC).
"When I heard of LBC's Great Wall of China challenge in September I knew it was for me," she said.
While Kevin is unable to accompany Esther on the five days a week trek, she knows he'll be with her in spirit.
"He's my inspiration for this challenge," she said.
"This is a great way for me to join 18 others and raise funds for Leukaemia and Blood Cancer New Zealand, helping others like Kevin and maybe helping to find a cure.
"It'll be a tough challenge, but nothing compared to what Kevin has been going through."
Community, family and friends have rallied around the McHardys, who are funding the $5000 for Esther's trip to China themselves.
"Everything I raise is going to LBC, and I've approached businesses and hope others will contribute to the cause," she said.
Esther said Dannevirke's Activate Gym had helped her prepare for the difficult Great Wall walk.
"I'm there four times a week and also go out walking both the Adelaide Rd and Tipapakuku blocks to get fit," she said.
The Norsewood Kiwi Sock Company has donated a pair of socks to each of the 19 walkers in the Leukaemia and Blood Cancer New Zealand colours, another example of the amazing support from our local community.
As well as the difficult terrain of the Great Wall, including unrestored sections, with many steep ascents and descents and thousands of steps along the way, Esther and Kevin have been delighted with the funds from the sale of a limited-edition calendar, Boys 'N' Toys, which will be launched at Dannevirke Barrelhouse Restaurant and Bar on Friday, July 21.
Proceeds will go to Leukaemia and Blood Cancer New Zealand.
"On the night, money from raffles and auctions will go to Dannevirke Cancer Support and we're grateful for the support of the Barrelhouse, Anderson Autos and MCI and Associates," Esther said.
For Kevin, the support has been humbling.
"Esther and I manage to carry on doing day-to-day things and I have good days and bad," he said.
"We make the most of the good days."
You can help
Every day, six more children and adults in New Zealand are diagnosed with a blood cancer such as leukaemia, lymphoma and myeloma. You can assist them.
A tax-deductible donation can be made directly to LBC and recorded under Esther McHardy's name. The link is https./www.leukaemia.org.nz
Click on "get involved, community fundraising" and scroll down to "search for a fundraiser", click on McHardy-Esther and click the red donate button.
You can also send your donation to Esther McHardy, 71 Gregg St, Dannevirke. Please make out cheques to LBC.
You can purchase a Dannevirke Boys 'N' Toys calendar at a fundraising evening at the Barrelhouse Restaurant and Bar on Friday, July 21, at 6.30pm.
What is myeloma?
Myeloma, also known as multiple myeloma or plasma cell myeloma, is a cancer of plasma cells (mature B-lymphocytes) that usually arises in the bone marrow.
Myeloma develops when plasma cells undergo a malignant (cancerous) change and become myeloma cells. These myeloma cells multiply without any proper order, forming collections known as tumours that accumulate in different parts of the body, most commonly in the bone marrow and on the surfaces of different bones in the body.
Myeloma is treatable, but incurable.